Problem: Christopher starts counting at 36, and he counts by fours. If 36 is the 1st number that Christopher counts. what is the 14th number that he counts?
Explanation: What is the first number that he counts? $36$ What is the second number that he counts? $\begin{align*}&36 + 4 \\ &= 40\end{align*}$ What is the third number that he counts? $\begin{align*}&36 + 4 + 4 \\ &= 36 + (2 \times 4) \\ &= 44\end{align*}$ What is the 14th number that he counts? $\begin{align*}&36 + (13\times4) \\ &= 36 + 52 \\ &= 88\end{align*}$